Field of the Disclosure
This disclosure relates to transparent access of data stored in databases comprising in-memory database.
Description of the Related Art
Data accessed/processed by various applications and/or services can be stored based on the age, importance, and/or any other factors related to the data in databases. For example, data that is important and/or frequently used, e.g., operation-relevant (or “hot”) data can be stored in fast, expensive storage media that can be quickly accessed, whereas data that is less relevant or less-frequently accessed (or “cold” data) can be stored in a slow, less expensive storage media. The Hot data can occupy top levels of storage hierarchy so that it can be easily accessed. Data “temperature” (“hot” or “cold”) can be assigned to the data based on usage, access, storage media, and/or any other factors.
The data can be stored redundantly at different levels of a storage hierarchy. However, it is preferable that only the hot data occupy top level(s) of storage hierarchy to save costs. After data temperature has been assigned to particular business object data and appropriate data storage location has been determined, the data can be appropriately queried/accessed. However, given the multiple temperatures of the stored data, it is difficult to determine how to optimally access the data at different storage levels, so that data queries load and/or process correct portions of “hot” and/or “cold” data.
Some conventional approaches to resolving this problem involve the user specifying whether cold data is to be considered or not. This is not feasible as the user typically is not aware of the temperature that has been assigned to the data and hence, is not able to identify whether cold data needs to be queried. This can lead to the end user not receiving the data the user requested (e.g., the user can be forced to re-run the query with a lower temperature delimiter), performance penalties due to unnecessarily evaluating data of higher I/O latency, and processing of a higher data volume. Another conventional approach requests application logic to derive the determination of whether hot/cold data needs to be queried and change all access coding, so that hot and/or cold data is queried explicitly. Such approach is implementation- and cost-prohibitive.
Thus, the conventional approaches failed to provide transparent data access that can avoid (content-wise) unnecessary data load and processing costs without placing a decision burden on end users or application developers in deciding whether data of lower temperatures should be accessed.